The philosophers of the Middle Ages demonstrated both that the Earth did not exist and also that it was flat. Today they are still arguing about whether the world exists, but they no longer dispute about whether it is flat.

Blackjack was rescued in 1923 after two years on Wrangel Island. A supporting sledge turned back 75 mi (121 km) offshore but he and two men continued onward on one sledge living largely by his rifle on polar game for 96 days until his party reached the Mary Sachs in the autumn. However William Laird McKinley and others left on the ship suspected that he left deliberately anticipating that the ship would be carried off by moving ice as indeed happened.